Chemical pesticides are used in commercial agriculture, home gardening, residential use, and similar applications for the purpose of controlling insects and spiders. There are well-known environmental and health concerns associated with using chemical pesticides, herbicides, or fungicides. For example, in some instances, it has been proven that the long-term use of certain chemical pesticides creates environmental problems. A well-known example involved the ban of DDT in the United States.
Ongoing health concerns about chemical pesticides have given rise to an emerging market for “organic” pesticides. Insecticidal soap is a typical example of an organic pesticide in use today.
Organic pesticides are generally deemed to be less effective than chemical pesticides. There is a trade-off when comparing one to the other. Chemical pesticides have a higher level of toxicity and provide better pest control. However, higher toxicity also heightens environmental concerns. The same level of environmental concern does not attach to organic pesticides, but at the price of effective pest control.
Hope cones contain lupulin glands that have two important bittering substances: alpha acids and beta acids. These acids are sometimes called humulones and lupulones, respectively. Hop acids were initially used as a preservative agent for beer prior to the existence of refrigeration. Today, they are primarily used to create the bitter taste and flavor of beer.
The term “hop acids,” as used here, means alpha acids, beta acids, mixtures of these acids, and/or other components found in hop extracts; for example, beta fraction, essential oils, waxes, and uncharacterized resins. The term “hop acids” also includes all forms of modified hop acids; for example, iso-alpha acids, tetra-hydro-iso-alpha acids, rho-iso-alpha acids, hexa-hydro-iso-alpha acids, and hexa-hydro-beta acids. As is well known, alpha acids consist of mixtures of analogues, primarily humulone, cohumulone, adhumulone, and other minor constituents. Similarly, beta acids consist of mixtures of analogues, primarily lupulone, colupulone, adlupulone, and other minor constituents. For these reasons, alpha and beta acids are referred to in the plural.
A number of companies are in the business of producing hop extracts for the brewing industry. These extracts come from the hops that are grown in various regions of the world. In some respects, the hop extract industry is a combination of agriculture and chemistry. On the agricultural side, hop growers have many of the same kinds of problems with pests as the growers of other food products. For example, spider mites, which are a common agricultural pest, are also a problem for hop growers.
Agricultural crops are also affected by powdery mildew, mold, and other kinds of blight or disease. Powdery mildew is particularly a problem for hop growers.
Given that people have been drinking hop acids as part of beer for many centuries, hop acids are a proven organic consumable. Hops are one of the basic ingredients of beer and, as such, hops and hop extracts are considered GRAS (Generally Recognized As Safe) by the U.S. Food and Drug Administration (“FDA”).
Those who work with hop extracts have discovered that the beta fraction of hop acids dissolved in ethanol or xylene can be toxic to spider mites. Hop acids and other components of hop extracts are not highly soluble in water, but are quite soluble in non-aqueous solvents like ethanol or xylene. However, such non-aqueous solvents are undesirable carriers for the application of pesticides to plants. Therefore, while water is an essential carrier for pesticide application to plants, because of solubility problems, water is not easy to use as a carrier if hop acids are the active agent.
The present invention provides a way to use water as the carrier for delivering hop acids as a pesticide, fungicide, or the like.